What is DN (Distinguished Name)?

DN stands for Distinguished Name and is an identifier used to identify entities in a computer system. It is used in many applications, such as access control, encryption, and authentication. DNs are an important part of the computer security infrastructure and are used to represent and identify users, computers, services, domains, and other resources in an enterprise network.

Understanding DN Structure

A DN is composed of a series of components, called Relative Distinguished Names (RDN). Each RDN is composed of one or more Attribute Types and Values. Attribute Types are specified using an attribute specification language, such as the X.500 attributes schema. Some of the most common attributes in a DN are the CN (Common Name), OU (Organizational Unit), O (Organization), C (Country), and ST (State). Each of these attributes has a corresponding value, such as “John Doe” for the CN, or “IT Department” for the OU.

The components of the DN are arranged in a hierarchical hierarchy. Each component is located above the other components, making it easy to distinguish between multiple identities within the same network. The DN of a user or service might look something like this: CN=John Doe, OU=IT Department, O=MyCompany, C=US, ST=California.

DN Formats and Usage

There are several different formats used to represent DNs. The most common is the X.500 format, which is used by most enterprise directory services, such as Microsoft Active Directory or LDAP. This format consists of a full DN (Distinguished Name), followed by the RDN (Relative Distinguished Name) components.

DNs are often used as user IDs or as part of security certificates. A user must possess a valid certificate and further authentication may be required in order to access certain parts of a network or services. Additionally, many authentication protocols use DNs for authentication, such as Kerberos and Simple Authentication and Security Layer (SASL). DNs are also used in various encryption protocols, such as SSL/TLS and S/MIME.

Summary

DN stands for Distinguished Name and is an identifier used to identify entities in a computer system. DNs are composed of a series of components called Relative Distinguished Names (RDN) and Attribute Types and Values. DNs are an important part of the computer security infrastructure and are used in many applications, such as user authentication, encryption, and access control. DNs are often used in authentication protocols and encryption protocols. They can also be used to represent user accounts and services in an enterprise network.